Iconian
gateway Highly advanced transporting device through which it is
possible to traverse vast distances in an instant, constructed by the Iconian
civilization 200,000 years ago (TNG: "Contagion", DS9: "To the
Death").
The technology may be related to the space-folding
transporter.

Ico-spectrogram
Geological test that may be used to confirm dilithium deposits in a planet's
crust (TNG: "Pen Pals").

IDFAcronym
for Inertial Damping Field,
a forcefield that is especially designed to compensate for acceleration forces within a starship.
Also referred to as inertial dampers. Several IDF generators are
distributed across a Federation starship (TNG: "Cause and Effect",
"The Chase", "Gambit", DS9: "Playing God",
"For the Uniform", "The Ship", VOY: "The Cloud").
Although the purpose and principle is similar, the IDF works
independently of the SIF. Without the IDF, the crew would virtually be
crushed when the ship accelerates. The STTNG Technical Manual
introduces a response delay, justifying "why our crew
is occasionally knocked out of their chairs during battle or
other drastic maneuvers despite the IDF." In DS9: "The Ship"
it was impressively shown what happens in case of an IDF failure. The Jem'Hadar
crew was found dead, with all their bones smashed because of the
acceleration.

Imaging
chamber Installation in the sickbay of an NX-class vessel. The
chamber is used for diagnostic radiography (ENT).A 22nd century equivalent to X-ray or MRT chambers.

Immersion
shield Deflector field technology designed for use in high-density
environments like the atmosphere of a gas giant or a deep ocean (VOY:
"Extreme Risk", "Thirty Days").

Impulse drivePropulsion system for sublight speeds. The fusion reaction generates a highly excited plasma. This plasma can be employed for
propulsion, or can be diverted through the EPS
so as to supply other systems (generic).On Federation starships the
impulse drive usually consists of a fusion reactor, an accelerator, a driver coil assembly and an
exhaust director. The accelerated plasma is passed
through the driver coils, thereby generating a subspace
field that enhances the propulsive
effect (STTNG Technical Manual).
In The Physics of Star Trek Lawrence Krauss discusses the amount
of fuel required for impulse speed, based on the energy gained by
the fusion reaction, and considering that mass significantly
increases at relativistic speeds. His result is that much more
fuel than the ship's mass is required to accelerate the ship to
high sublight speed. Focusing on real-life principles rather than on Trek tech, Krauss did not take into account that the
subspace field generated in the driver coils lowers the apparent
mass. The TNGTM, however, states that the
subspace driver coil was introduced as late as in the Ambassador
class, although it must have existed earlier according to Krauss's
calculations. One could suggest that the warp coils could
generate a subspace field below 1 cochrane in order to achieve
sublight propulsion or at least facilitate impulse propulsion. Yet, according to the TNGTM, the
efficiency of the warp coils drops drastically below Warp 1
and therefore the warp drive would not be "wasted" for this
purpose.

Impulse
manifold Part of a starship's impulse power and propulsion system
(ENT).

Impulse
power Informal designation for the power generated in the impulse
(fusion) reactor. Its output is usually considerably lower than that of the
warp core (generic).

Impulse speed Sublight speed achieved with the impulse drive, usually referred to in fractions of
"full impulse" (generic).
While traveling at warp, relativistic
effects like time dilation are eluded due
to the presence of the "protective" warp field, as the TNGTM
explains. At impulse speeds these effects are inevitable and would become
significant when traveling above approx. 0.25c for some time. But since the
impulse drive is customarily used only for a matter of minutes or at most hours,
the resulting time dilation is still no big deal and was never mentioned in an
episode.

Interface probe
Robotic device that is remote-controlled using a telepresence technology. The
telepresence unit including a sensor suit could be connected to Geordi La Forge's
neural VISOR interface (TNG: "Interface").

Interlink
node Cybernetic implant in every Borg drone that
enables communication with the Collective (VOY: "Counterpoint",
"Survival Instinct", "Ashes to Ashes", "Unimatrix Zero",
"Endgame"). See also neural interface.In "Ashes to Ashes" the interlink nodes of former Borg drones Rebi
and Azan were called "neural interface" (when they cheated in a
kadiskot game). In "Endgame" Admiral Janeway used a special neural
interface to infiltrate and poison the hive mind.

Intermix ratio
Ratio of matter to antimatter to be injected into a warp
core (TNG: "Coming of Age", TNGTM).Read Power & Propulsion
for more about the intermix ratio problem and whether Wesley was really right
about it.

Internal
transporter Built-in transporter of the Borg Drone named One. Enables
One to beam to some other place, taking the whole transporter with him (VOY:
"Drone").The perhaps most unlikely technology ever shown. But in "Star Trek
Nemesis" Geordi and Data built something quite similar, the emergency
transporter.

Interphase generatorSpecial cloaking device that
manipulates the molecular structure of matter in a way that it is
transferred ("phased") into a quasi-parallel space. Matter cloaked with an
interphase generator is not only invisible to conventional
natural and artificial sensors, it is also able to penetrate
normal matter (TNG: "The Next Phase", "Pegasus").An interphase generator was installed in the USS Pegasus in
2358, although cloaking devices are prohibited in the Federation
according to the Algeron Treaty (TNG: "The Pegasus").
The Romulans tested such a cloaking device in 2368. When the
experiment failed and the Enterprise arrived to assist the
Romulan ship, Geordi and Laren were affected by this device and
disappeared. However, while being in phase, they were still able
to stand on the floor and breathe normal air (TNG: "The Next
Phase"). The shown effects are much too inconsistent to
determine whether the cloaked object disappears to a parallel
dimension or to subspace or anywhere else.

Interphasic scanner Special
hand-held sensor device used to detect objects or organisms that are out of phase and hence invisible to the naked eye or to conventional equipment
like tricorders (TNG: "Phantasms").

Intraship beaming
23rd century designation of the procedure commonly known as site-to-site
transport in the 24th century. It was deemed dangerous and required
pinpoint accuracy in order to be successful (TOS: "Day of the Dove").It does not seem to be a big deal beaming someone at most 200 meters across
the ship when transporting the same person to a planet surface thousands of
kilometers away is almost always safe, even through meters of solid rock. We may
rationalize the dangerous nature of intraship beaming nonetheless, because
starships probably have dedicated transporter channels. Their supposed exits to
space, the emitter pads, are
visible on most 24th century vessels. The exit of one of these channels may
need to point in direction of the planet, whereas there is naturally no such
channel available for arbitrary transport destinations inside the ship.

Intruder alert Increased state of readiness on a Federation starship. Intruder
alert may be issued by any crew member who has detected that the ship has been
boarded. It can also be triggered automatically by sensors (generic).

Invasive program Type
of a computer virus, particularly one devised on the Enterprise-D to destroy the
Borg. The program consisted of an insoluble puzzle that would have taken so many
resources to solve that it would have disabled the Borg Continuum. Its
implementation was eventually refused because of ethical concerns, as it would
have constituted an act of genocide (TNG: "I, Borg").Of course, the somewhat far-fetched rationale behind the virus is that, just
like in TOS: "I , Mudd", the Borg would not be able to cope with
something like "Every word I say is a lie", albeit probably on a more sophisticated
level.

Inverter Device used
by the Ansata terrorists on Rutia IV for space-folding transport. See also dimensional
shifter.

Ion cannon Generic
name for weapons that fire charge particles. The Mokra order in the Delta
Quadrant has placed more than 85 phased ion cannons on their homeworld (VOY:
"Resistance").

Ion trail Residue of
ionized particles that a starship traveling at impulse speed (or with any other
propulsion with ionized exhaust) leaves behind (generic).In TOS: "Spock's Brain" the Enterprise follows the ion trail that
is naturally left behind by the Eymorg ship with an ion drive. In "Star
Trek: "The Undiscovered Country" McCoy and Spock prepare a torpedo to
track the gaseous exhaust of the cloaked Klingon Bird-of-Prey at Uhura's
suggestion. We should assume that at latest since "Spock's Brain"
Starfleet ships have standard sensors for that purpose. But perhaps they are
just not suited for such a close range. On other occasions in Star Trek it seems
like "ion trail" is used synonymously with "warp
trail" or "warp signature", although at warp (meaning
conventional warp, not using
ion drive) the subspace distortion should be characteristic of a passing vessel,
rather than some sort of exhaust.

Isograted circuit
Technology obtained from a crashed 29th century timeship, introduced by Henry
Starling on Earth in 1969 (VOY: "Future's End").We do not know if and how much of this technology still exists in the restored
timeline.

Isolinear chip Nanotechnical
device used for data and software processing and storage in 24th
Federation computer
systems. Isolinear chips also serve as portable storage
devices (generic).According to the TNGTM optical signal
processing is employed in isolinear chips, and FTL signal
transfer is enabled when they are installed in a starship's computer core with
its subspace field. It is unknown why these chips are called
"isolinear", maybe this refers to the single (iso-)
crystalline structure of the optical layers.

Isomagnetic
disintegrator Large portable energy beam weapon. Such a weapon was
used by Picard's crew to defend the Ba'ku in 2375 ("Star Trek:
Insurrection").The disintegrator resembles a bazooka and is operated by Worf in a similar
fashion. However, it is not clearly stated in the movie that Worf's weapon is
the disintegrator, except for notes in secondary works.

IsotonUnit for the measurement of the explosive force of a
photon
torpedo or quantum torpedo
(VOY).This unit might be useful, yet it is not very precise. Since
"iso-" means "equal", it could represent an
equivalent mass of explosives, given in tons. It is very
improbable that the (metric?) tons refer to TNT, because present-day fission bombs are already in the range of hundreds of
kilotons of TNT. The unit probably does not apply to antimatter,
either, since a photon torpedo contains only a few kilograms of
it and in VOY: "Scorpion, Part II", Seven of Nine lists
"Voyager's weapons inventory: Photon torpedo complement 32,
Class-6 warheads. Explosive yield 200 isotons."
Isotons are
also mentioned in VOY: "The Omega Directive", where a
single photon torpedo casing can be armed to 80 isotons. Subsequently, there are
mentions of still higher yields each time. Isotons seem to share the fate of the
quads...